The numbers of British teenagers learning European languages fell again in this year's A-levels, prompting examiners to speak of a crisis in the subjects.

Entries in French declined to about 12,500 this year, and the number of candidates taking German dropped below 5,000. The number of entries for Spanish declined slightly, at 7,351 this year compared with 7,610 in 2011, although the trend over the last five years is up.

There was a modest rise in the take-up of other languages. Entries for A-level Polish rose from 844 last year to 923, and there were 3,425 entries for Mandarin, compared with 3,237 in 2011. Arabic, Japanese and Russian entries also climbed.

Andrew Hall, chief executive of the AQA exam board, said the drop in the number of people taking A-levels in traditional modern foreign languages was a real worry. "We have the euro economy in crisis – I think modern foreign languages are in the same place," he said.

There was no magic bullet to fix the problem, Hall said, but he welcomed the government's move this year to introduce modern languages in primary schools.

Mark Dawe, chief executive of the OCR exam board, said universities had made it clear they wanted students with qualifications in science and maths. "I'm not sure the message has been as strong around languages, so they could assist in this approach," he said.

There were 85,714 candidates taking maths this year. Maths has increased in popularity over the last five years and now accounts for nearly 10% of the total number of entries.

Russell Hobby, general secretary of the National Association of Head Teachers, said: "A strategy designed to promote modern foreign languages is overdue. From investigating the possibility of giving talented language teachers a 'golden hello' to setting up advisory networks, we must begin to raise the status of modern foreign languages so that our school leavers can take full advantage of the creative and commercial opportunities the rest of the world has to offer."

Prof Dame Athene Donald, chair of the Royal Society education committee, welcomed the increase in candidates taking science subjects. "In these times of economic hardship it should be with a great sense of relief that we see the numbers of students choosing to take science A-levels rising for yet another year.

"Scientific research and development provide the UK with genuine prospects for economic growth and I am delighted that many young people are aware of the opportunities that science qualifications offer them."

She said the Royal Society remained concerned that the current A-level system was too narrow, and suggested there should be a baccalaureate-style system to allow students to study more subjects.